what is difference between macbook and macbook pro

What is the difference between 1.HashMap and Hashtable?HashMap is not thread-safe and its operation method is not synchronizedHashMap allow key to be empty　　　　Hashtable is thread-safe and its operation method has been synchronized

Set (0.02 sec)mysql> INSERT into Testint values (336, 257);Query OK, 1 row affected, 1 Warning (0.02 sec)Mysql> select * from Testint;+------+------+| ID | col2 |+------+------+| 256 | 127 || 336 | 127 |+------+------+2 rows in Set (0.00 sec)mysql> INSERT into Testint values (336, 255);Query OK, 1 row affected, 1 warning (0.03 sec)Mysql> select * from Testint;+------+------+| ID | col2 |+------+------+| 256 | 127 || 336 | 127 || 336 | 127 |+------+------+3 Rows in Set (0.00 sec)Mysql>Take a loo

According to the content and according to the adjustment of the window you may not be clear, let's see, what is the difference between the bottom? 1, open Word, on the Table menu, "Insert" in the Select "Table" 2, we see the adjustment table according to the content and according to the window two types, these two types of inverted bottom

When it comes to wireless, some people think of wif some people think of WLAN, what is the difference between WiFi and WLAN? In short, WIFI is the acronym for Wireless Fidelity (wireless fidelity), a technology that allows computers, mobile phones, and so on to interconnect wirelessly. And WLAN refers to wireless LAN

What is the difference between static global variables and common global variables? What is the difference between static local variables and common local variables? What

What is the difference between Iphone6 mobile phone contract machine and bare metal? For the contract machine, I believe that everyone will be unfamiliar, in many outdoor billboards, you can see a variety of very attractive "0 yuan buy machine", advertising slogans, the contract machine is actually the network operato

1. What is the difference between the free communication function and the micro-letter telephone? Micro-mail phone mainly through the operator data channel (3G/4G or fixed network to WiFi) to achieve free call, in the operator 3G/4G network actually also need to pay mobile data costs. And the other side must install the micro-letter phone application, and

memory. Sleep mode is a newly added feature that combines the benefits of standby and hibernation. Computer knowledge What is the difference between computer hibernation and sleep? Sleep is the combination of the benefits of standby and hibernation, so the sle

Original link: http://blog.163.com/baibai_zheng/blog/static/51980755201022125325689/Introduction: Recently contacted Laravel database migration, the code Schema let me to the database and the difference between the two a bit of a circle, and then have this reprint.Creating a schema in MySQL seems to have the same effect as creating a database, which looks different in SQL Server and Orcal databases. At the moment I can only understand that schemaThe r

In the U disk, SSD and other solid-state storage products, flash chip particles is the core, which relates to product costs, life and speed. Flash chip particles are mainly three types, respectively, SLC, MLC, TLC, the difference between the three, as follows. What is the differen